I would agree lane discipline on Motorways sucks like a toothless parrot. As for driving too slowly I don't see A/B/main roads in this situation very often. 50 in a 50 limit seems fairly solid.
The introduction of the average speed cameras on the M3 have made this worse from my observation. People who were in lane 2-3 now stay in the same lane and drop down to 69mph. So we end up with undertaking, flashing and Lane 1 being left to lorries which is not such a bad thing for safety.
